Mailman 3 September 2018 - docs

[issue31305] 'pydoc -w import' report "no Python documentation found for 'import'"
by Karthikeyan Singaravelan 05 Jul '20

05 Jul '20

New submission from Karthikeyan Singaravelan <tir.karthi(a)gmail.com>: > Run "pydoc -w <name>" to write out the HTML documentation for a module to a file named "<name>.html". As mentioned in the help this works only for modules and since import is a keyword it throws an error. Maybe this could be added as an enhancement? Thanks ---------- nosy: +xtreak _______________________________________ Python tracker <report(a)bugs.python.org> <https://bugs.python.org/issue31305> _______________________________________

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[issue21333] Document recommended exception for objects that shouldn't be pickled
by Stefan Schwarzer 05 Jul '20

05 Jul '20

New submission from Stefan Schwarzer: I recently was confused whether to raise a `PicklingError` or `TypeError` in `__getstate__` if objects of my class can't and shouldn't be pickled. [1] Terry Reedy advised I should use `TypeError`. [2] I wonder if the `pickle` module documention should explicitly recommend using `TypeError` if a class wants to say that its objects can't be pickled. What do you think? [1] https://mail.python.org/pipermail/python-list/2014-April/670987.html [2] https://mail.python.org/pipermail/python-list/2014-April/671002.html ---------- assignee: docs@python components: Documentation messages: 217054 nosy: docs@python, sschwarzer priority: normal severity: normal status: open title: Document recommended exception for objects that shouldn't be pickled type: enhancement versions: Python 3.5 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue21333> _______________________________________

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[issue33864] collections.abc.ByteString does not register memoryview
by Jason Fried 04 Jul '20

04 Jul '20

New submission from Jason Fried <me(a)jasonfried.info>: Looking at the typing Module docs in the section for ByteString This type represents the types bytes, bytearray, and memoryview. But collections.abc.ByteString does not have memoryview registered. Is it because memoryview doesn't support .index()? ---------- assignee: docs@python components: Documentation messages: 319557 nosy: docs@python, fried, lukasz.langa priority: normal severity: normal status: open title: collections.abc.ByteString does not register memoryview type: behavior versions: Python 3.6, Python 3.7, Python 3.8 _______________________________________ Python tracker <report(a)bugs.python.org> <https://bugs.python.org/issue33864> _______________________________________

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[issue17805] No such class: multiprocessing.pool.AsyncResult
by Takafumi Arakaki 03 Jul '20

03 Jul '20

New submission from Takafumi Arakaki: Document mentions AsyncResult but there is no such class. http://docs.python.org/2/library/multiprocessing.html#multiprocessing.pool.… You can check it by simply running: python -c 'from multiprocessing.pool import AsyncResult' I think it means ApplyResult so I made a patch (attached). Note that there managers.py also uses name 'AsyncResult': % hg grep AsyncResult Doc/library/multiprocessing.rst:83232:.. class:: AsyncResult Lib/multiprocessing/managers.py:81039: 'apply_async': 'AsyncResult', Lib/multiprocessing/managers.py:81039: 'map_async': 'AsyncResult', Lib/multiprocessing/managers.py:81039: 'starmap_async': 'AsyncResult', Lib/multiprocessing/managers.py:81039:SyncManager.register('AsyncResult', create_method=False) Probably renaming them would be better? ---------- assignee: docs@python components: Documentation files: ApplyResult.patch keywords: patch messages: 187466 nosy: docs@python, tkf priority: normal severity: normal status: open title: No such class: multiprocessing.pool.AsyncResult versions: Python 2.6, Python 2.7, Python 3.1, Python 3.2, Python 3.3, Python 3.4, Python 3.5 Added file: http://bugs.python.org/file29954/ApplyResult.patch _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue17805> _______________________________________

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[issue23427] Python should expose command when invoked with -c
by Jan-Philip Gehrcke 29 Jun '20

29 Jun '20

New submission from Jan-Philip Gehrcke: When Python is invoked with the `-c command` switch, the command string does not get exposed in sys.argv: $ python -c "import sys; print(sys.argv)" ['-c'] $ python -c "import sys; print(sys.argv)" arg1 ['-c', 'arg1'] The command string does not get exposed anywhere, AFAIK, so it is inaccessible from within Python programs. There might be application scenarios in which it is useful to access the command string, such as for debugging purposes. One scenario is when a Python session should be able to "re-spawn" itself in a subprocess (I came across this question on StackOverflow: http://stackoverflow.com/q/28412903/145400) I propose to make the command string accessible. If you agree that it might make sense, the question is *how/where* to expose it. One possible way is to retain it in sys.argv, as in this example: $ python -c "import sys; print(sys.argv)" "arg1" ['-c', 'import sys; print(sys.argv)', 'arg1'] The current sys.argv docs say > If the command was executed using the -c command line option to > the interpreter, argv[0] is set to the string '-c'. This sentence could then be adjusted to "[...], argv[0] is set to the string '-c', and argv[1] contains the command." This method breaks existing applications that are started with the -c method and that consume command line arguments in a sys.argv[1:] fashion. The tests in Lib/test/test_cmd_line.py all pass, however. A second method would be to change sys.argv[0] from '-c' to '-c command'. This would break existing applications that check for sys.argv[0] == 'c'. A third method would be to leave sys.argv as it is, and expose the command with a new attribute in the sys module. I have attached a patch for variant 1 (passes all tests in Lib/test/test_cmd_line.py), to demonstrate which code is affected: the translation from the "real" argv to sys' argv is triggered in Modules/main.c. The patch does not change behavior of '-m' (it's funny, however, that the current version of main.c at first replaces the module string with '-m', whereas the runpy module later on replaces '-m' with the path to the module file anyway.). As a side node, I figure that the sys.argv documentation should be adjusted to properly reflect the -m behavior, which is: $ ./python -m testmodule foo testmodule sys.argv: ['/data/local/pythondev/pythontip/cpython/testmodule.py', 'foo'] Let me hear your comments, and I am willing to work on code and doc patches, thanks! ---------- assignee: docs@python components: Documentation, Interpreter Core files: sys_argv_cmd.patch keywords: patch messages: 235633 nosy: docs@python, georg.brandl, haypo, jgehrcke, pitrou priority: normal severity: normal status: open title: Python should expose command when invoked with -c type: enhancement versions: Python 3.5, Python 3.6 Added file: http://bugs.python.org/file38065/sys_argv_cmd.patch _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue23427> _______________________________________

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[issue33553] possible documentation improvement proposal for multiprocessing
by Derek Kim 28 Jun '20

28 Jun '20

New submission from Derek Kim <bluewhale8202(a)gmail.com>: >>> from multiprocessing import Pool >>> p = Pool(5) >>> def f(x): ... return x*x ... >>> p.map(f, [1,2,3]) This example in the document is confusing because this is already wrong code when run with fork method even if you run it as a script. With fork start method, f should be defined before p is created. Also, just advising that one shouldn't use interactive shell and should run multiprocessing code in if __name__ == '__main__' is not informative becuase those conditions are generally no problem with fork method. Can I try improving the documentation? ---------- assignee: docs@python components: Documentation messages: 316892 nosy: Derek Kim, docs@python priority: normal severity: normal status: open title: possible documentation improvement proposal for multiprocessing versions: Python 3.8 _______________________________________ Python tracker <report(a)bugs.python.org> <https://bugs.python.org/issue33553> _______________________________________

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[issue31082] reduce takes iterable, not just sequence
by Stefan Pochmann 28 Jun '20

28 Jun '20

New submission from Stefan Pochmann: functools.reduce has a parameter called "iterable" and it only needs to be an iterable, not a sequence. The paragraph documenting it says "sequence" instead of "iterable" six times: https://docs.python.org/3/library/functools.html#functools.reduce The help shown by executing "help(functools.reduce)" in Python additionally actually names the parameter "sequence" in the signature. ---------- assignee: docs@python components: Documentation messages: 299520 nosy: Stefan Pochmann, docs@python priority: normal severity: normal status: open title: reduce takes iterable, not just sequence type: enhancement versions: Python 3.6, Python 3.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue31082> _______________________________________

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[issue30951] Documentation error in inspect module
by Alex Vig 25 Jun '20

25 Jun '20

New submission from Alex Vig: The documentation for co_names in the inspect module is: "tuple of names of local variables" Local variable names are however in co_varnames while co_names contains global variable names. This description should read: "tuple of names of global variables" Relevant StackOverflow post here: https://stackoverflow.com/q/45147260/1953800 ---------- assignee: docs@python components: Documentation messages: 298545 nosy: Alex Vig, docs@python priority: normal severity: normal status: open title: Documentation error in inspect module versions: Python 2.7, Python 3.3, Python 3.4, Python 3.5, Python 3.6, Python 3.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue30951> _______________________________________

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[issue17589] Make documentation about macros in C API explicit about rvalue vs statement
by Larry Hastings 25 Jun '20

25 Jun '20

New submission from Larry Hastings: CPython API "functions" implemented as macros can expand into either rvalues or statements. Most expand into statements (often using the do {} while (0) syntactic sugar trick), but occasionally they're legal as rvalues. As of this writing Py_INCREF works as an rvalue. But discussion on another tracker issue (#17206) proposes changing the implementation in such a way that it will only be usable as a statement. Although it's mildly unlikely, it's certainly possible that this will break somebody's code. I propose that the documentation make an explicit ruling on whether macros are usable as rvalues or as statements. Perhaps a blanket statement would suffice, "all macros are only supported for use as statements except where explicitly noted", then annotate specific macros that are supported for use as rvalues. Though that raises the question of acknowledging in the documentation that some things are macros--I think the documentation glosses over that fact right now. Note: I added you three (Georg, Mark, Martin) as I thought you might have an opinion on this one way or the other. If you're not interested, my apologies. ---------- assignee: docs@python components: Documentation messages: 185646 nosy: Mark.Shannon, docs@python, georg.brandl, larry, loewis priority: normal severity: normal stage: needs patch status: open title: Make documentation about macros in C API explicit about rvalue vs statement type: enhancement versions: Python 3.4 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue17589> _______________________________________

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[issue21508] C API PyArg_ParseTuple doc is innacurate
by Steve 25 Jun '20

25 Jun '20

New submission from Steve: PyArg_ParseTuple is defined as returning an "int", but the documentation talks about returning a true/false value, and failling on false. In addition to being inaccurate, considering that most other functions fail on !=0 ("true"), it can lead to confusion. Doc: int PyArg_ParseTuple(PyObject *args, const char *format, ...) Parse the parameters of a function that takes only positional parameters into local variables. Returns true on success; on failure, it returns false and raises the appropriate exception. ---------- assignee: docs@python components: Documentation messages: 218536 nosy: Banger, docs@python priority: normal severity: normal status: open title: C API PyArg_ParseTuple doc is innacurate type: enhancement versions: Python 3.3, Python 3.4, Python 3.5 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue21508> _______________________________________

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